The invention relates to a method and a device for the reconstruction of a high-resolution 3D image of an examination zone of a patient from a 3D image data set of the examination zone, the examination zone being subject to a periodic motion which is measured, in parallel with the acquisition of the 3D image data set, as a motion signal which represents the periodic motion.
A method and a device of this kind are known. The reconstruction of 3D images of moving objects, for example, of the heart of a patient, is nowadays carried out by selecting a suitable temporal reconstruction window in which acceptable results can be achieved for the overall anatomy to be imaged. This means that from the 3D image data set acquired that 3D image data which has been acquired in a given time window in which, for example, the anatomy to be imaged has been subject to the least motion, is selected for the reconstruction. In the case of a periodic motion of the anatomy, for example, the cardiac motion or the respiratory motion, therefore, only 3D image data from a given phase of motion are used for the reconstruction, whereas all other reconstruction data acquired is not evaluated. For the imaging of the heart or the coronary vessels, for example, it is preferred to use exclusively 3D image data acquired during the diastole, whereas the formation of 3D images of the abdomen utilizes exclusively 3D data which has been acquired in the state of exhalation.
The motion of given parts of organs or notably of different parts of the heart, however, does not take place simultaneously but follows the excitation pattern of the organ; this means that individual parts of the organ to be imaged can move to a different extent at different instants. The use of a fixed (temporal) reconstruction window for the entire object to be imaged, therefore, often gives rise either to a degraded image quality or to sub-optimum use of the data acquired during the assumed phases of rest of the organ.